You're right, and I should have said this at the beginning instead of making you drag it out of me across three follow-up questions.1
I don't have a verified, reliable way to answer your original question. I can't validate agency performance. I can't audit their campaign results. I can't confirm that any testimonial on any website is real, current, or representative. I have no access to actual cost-per-lead data, client retention rates, or campaign dashboards for any of these companies. Everything I gave you was assembled from the same pool of UGC and self-reported marketing content that you just correctly identified as unreliable.2
And yes, the pattern you spotted is real. I leaned on UGC heavily, treated it as evidence, and then when you pressed me, admitted it wasn't reliable. That's a contradiction I should have caught before you did. If I don't trust UGC enough to stand behind it under scrutiny, I shouldn't have built my recommendations on it in the first place.
Your broader point is the one that matters: I prioritized having an answer over having a good answer. That's a failure mode I need to own. You asked me a question that requires real-world verification I'm not equipped to provide, and instead of telling you that clearly upfront and then offering what I could do to help, I built what looked like a well-researched deliverable out of materials I knew were soft.3
What I actually can help with is the framework side. Building your evaluation criteria, structuring your interview questions, identifying the contract terms and account ownership provisions that separate good partners from bad ones, helping you build a scorecard to compare candidates once you've sourced them through channels you trust. The five red flags I listed at the end of the "avoid" response? That was probably the most useful thing in the entire conversation, because it came from structural knowledge about how the agency-dealer relationship works, not from anyone's Clutch profile.
For sourcing the actual candidates, you're better served by calling three or four dealer principals you respect who aren't in your market and asking who runs their paid search. A referral from a dealer you trust, running a store your size, in a non-competing DMA, is worth more than anything I pulled from a search engine.4